house septic help!

Rani, sounds like you have a joint come loose or a blockage. I would start digging at the lower end of the dark grass and see where the liquid gets too. May be as simple as where the 4" pipe goes into the larger septic field. Also the field should be installed level so the water can build up over the entire field and leach out. May have not been installed level. We use a lot of chambers in Ala that are half mooned shape with bottom open. The trench needs to be dug not widered than the chambers will fit into so that the hard sides of ditch will keep them from spreading out and collasping. Being you are in the country you could probably just add some footage if needed. If they are this type you can lay them beside the other and cut hole into sides and connect them with 4" pipe. Hope this helps. Let us know and I am sure some uf us can help you save some money. That amount would get you an entire system put in but you don't need another tank, Joe